Discovery matcher

describe "#by_category_id named scope"do
let(:given_category) do Factory.create(:given_category)
end
let(:product_in_given_category) doFactory.create(
:product,
:categories => [given_category]
)
end
let(:product_not_in_given_category) doFactory.create(
:product,
:categories => [Factory.create(:category)]
)
end# This might be tricky to redefine subject as the finder result# but in this way we can delegate the matcher to subject and # avoid writing test descriptions.
subject { described_class.by_category_id(given_category.id) }
it { should discover(product_in_given_category) }
it { should_not discover(product_not_in_given_category) }
end